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Use end-of-line comments in planner.cpp

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2.0.x
Scott Lahteine 7 years ago
parent 6c7a17dba6
commit 8f57e098de
1 changed files with 177 additions and 177 deletions
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Marlin/src/module/planner.cpp
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@ -406,300 +406,300 @@ void Planner::init() {
register const uint8_t* ptab = inv_tab;
__asm__ __volatile__(
/* %8:%7:%6 = interval*/
/* r31:r30: MUST be those registers, and they must point to the inv_tab */
// %8:%7:%6 = interval
// r31:r30: MUST be those registers, and they must point to the inv_tab
" clr %13" "\n\t" /* %13 = 0 */
" clr %13" "\n\t" // %13 = 0
/* Now we must compute */
/* result = 0xFFFFFF / d */
/* %8:%7:%6 = interval*/
/* %16:%15:%14 = nr */
/* %13 = 0*/
// Now we must compute
// result = 0xFFFFFF / d
// %8:%7:%6 = interval
// %16:%15:%14 = nr
// %13 = 0
/* A plain division of 24x24 bits should take 388 cycles to complete. We will */
/* use Newton-Raphson for the calculation, and will strive to get way less cycles*/
/* for the same result - Using C division, it takes 500cycles to complete .*/
// A plain division of 24x24 bits should take 388 cycles to complete. We will
// use Newton-Raphson for the calculation, and will strive to get way less cycles
// for the same result - Using C division, it takes 500cycles to complete .
" clr %3" "\n\t" /* idx = 0 */
" clr %3" "\n\t" // idx = 0
" mov %14,%6" "\n\t"
" mov %15,%7" "\n\t"
" mov %16,%8" "\n\t" /* nr = interval */
" tst %16" "\n\t" /* nr & 0xFF0000 == 0 ? */
" brne 2f" "\n\t" /* No, skip this */
" mov %16,%8" "\n\t" // nr = interval
" tst %16" "\n\t" // nr & 0xFF0000 == 0 ?
" brne 2f" "\n\t" // No, skip this
" mov %16,%15" "\n\t"
" mov %15,%14" "\n\t" /* nr <<= 8, %14 not needed */
" subi %3,-8" "\n\t" /* idx += 8 */
" tst %16" "\n\t" /* nr & 0xFF0000 == 0 ? */
" brne 2f" "\n\t" /* No, skip this */
" mov %16,%15" "\n\t" /* nr <<= 8, %14 not needed */
" clr %15" "\n\t" /* We clear %14 */
" subi %3,-8" "\n\t" /* idx += 8 */
/* here %16 != 0 and %16:%15 contains at least 9 MSBits, or both %16:%15 are 0 */
" mov %15,%14" "\n\t" // nr <<= 8, %14 not needed
" subi %3,-8" "\n\t" // idx += 8
" tst %16" "\n\t" // nr & 0xFF0000 == 0 ?
" brne 2f" "\n\t" // No, skip this
" mov %16,%15" "\n\t" // nr <<= 8, %14 not needed
" clr %15" "\n\t" // We clear %14
" subi %3,-8" "\n\t" // idx += 8
// here %16 != 0 and %16:%15 contains at least 9 MSBits, or both %16:%15 are 0
"2:" "\n\t"
" cpi %16,0x10" "\n\t" /* (nr & 0xf00000) == 0 ? */
" brcc 3f" "\n\t" /* No, skip this */
" swap %15" "\n\t" /* Swap nibbles */
" swap %16" "\n\t" /* Swap nibbles. Low nibble is 0 */
" cpi %16,0x10" "\n\t" // (nr & 0xf00000) == 0 ?
" brcc 3f" "\n\t" // No, skip this
" swap %15" "\n\t" // Swap nibbles
" swap %16" "\n\t" // Swap nibbles. Low nibble is 0
" mov %14, %15" "\n\t"
" andi %14,0x0f" "\n\t" /* Isolate low nibble */
" andi %15,0xf0" "\n\t" /* Keep proper nibble in %15 */
" or %16, %14" "\n\t" /* %16:%15 <<= 4 */
" subi %3,-4" "\n\t" /* idx += 4 */
" andi %14,0x0f" "\n\t" // Isolate low nibble
" andi %15,0xf0" "\n\t" // Keep proper nibble in %15
" or %16, %14" "\n\t" // %16:%15 <<= 4
" subi %3,-4" "\n\t" // idx += 4
"3:" "\n\t"
" cpi %16,0x40" "\n\t" /* (nr & 0xc00000) == 0 ? */
" brcc 4f" "\n\t" /* No, skip this*/
" cpi %16,0x40" "\n\t" // (nr & 0xc00000) == 0 ?
" brcc 4f" "\n\t" // No, skip this
" add %15,%15" "\n\t"
" adc %16,%16" "\n\t"
" add %15,%15" "\n\t"
" adc %16,%16" "\n\t" /* %16:%15 <<= 2 */
" subi %3,-2" "\n\t" /* idx += 2 */
" adc %16,%16" "\n\t" // %16:%15 <<= 2
" subi %3,-2" "\n\t" // idx += 2
"4:" "\n\t"
" cpi %16,0x80" "\n\t" /* (nr & 0x800000) == 0 ? */
" brcc 5f" "\n\t" /* No, skip this */
" cpi %16,0x80" "\n\t" // (nr & 0x800000) == 0 ?
" brcc 5f" "\n\t" // No, skip this
" add %15,%15" "\n\t"
" adc %16,%16" "\n\t" /* %16:%15 <<= 1 */
" inc %3" "\n\t" /* idx += 1 */
" adc %16,%16" "\n\t" // %16:%15 <<= 1
" inc %3" "\n\t" // idx += 1
/* Now %16:%15 contains its MSBit set to 1, or %16:%15 is == 0. We are now absolutely sure*/
/* we have at least 9 MSBits available to enter the initial estimation table*/
// Now %16:%15 contains its MSBit set to 1, or %16:%15 is == 0. We are now absolutely sure
// we have at least 9 MSBits available to enter the initial estimation table
"5:" "\n\t"
" add %15,%15" "\n\t"
" adc %16,%16" "\n\t" /* %16:%15 = tidx = (nr <<= 1), we lose the top MSBit (always set to 1, %16 is the index into the inverse table)*/
" add r30,%16" "\n\t" /* Only use top 8 bits */
" adc r31,%13" "\n\t" /* r31:r30 = inv_tab + (tidx) */
" lpm %14, Z" "\n\t" /* %14 = inv_tab[tidx] */
" ldi %15, 1" "\n\t" /* %15 = 1 %15:%14 = inv_tab[tidx] + 256 */
/* We must scale the approximation to the proper place*/
" clr %16" "\n\t" /* %16 will always be 0 here */
" subi %3,8" "\n\t" /* idx == 8 ? */
" breq 6f" "\n\t" /* yes, no need to scale*/
" brcs 7f" "\n\t" /* If C=1, means idx < 8, result was negative!*/
/* idx > 8, now %3 = idx - 8. We must perform a left shift. idx range:[1-8]*/
" sbrs %3,0" "\n\t" /* shift by 1bit position?*/
" rjmp 8f" "\n\t" /* No*/
" adc %16,%16" "\n\t" // %16:%15 = tidx = (nr <<= 1), we lose the top MSBit (always set to 1, %16 is the index into the inverse table)
" add r30,%16" "\n\t" // Only use top 8 bits
" adc r31,%13" "\n\t" // r31:r30 = inv_tab + (tidx)
" lpm %14, Z" "\n\t" // %14 = inv_tab[tidx]
" ldi %15, 1" "\n\t" // %15 = 1 %15:%14 = inv_tab[tidx] + 256
// We must scale the approximation to the proper place
" clr %16" "\n\t" // %16 will always be 0 here
" subi %3,8" "\n\t" // idx == 8 ?
" breq 6f" "\n\t" // yes, no need to scale
" brcs 7f" "\n\t" // If C=1, means idx < 8, result was negative!
// idx > 8, now %3 = idx - 8. We must perform a left shift. idx range:[1-8]
" sbrs %3,0" "\n\t" // shift by 1bit position?
" rjmp 8f" "\n\t" // No
" add %14,%14" "\n\t"
" adc %15,%15" "\n\t" /* %15:16 <<= 1*/
" adc %15,%15" "\n\t" // %15:16 <<= 1
"8:" "\n\t"
" sbrs %3,1" "\n\t" /* shift by 2bit position?*/
" rjmp 9f" "\n\t" /* No*/
" sbrs %3,1" "\n\t" // shift by 2bit position?
" rjmp 9f" "\n\t" // No
" add %14,%14" "\n\t"
" adc %15,%15" "\n\t"
" add %14,%14" "\n\t"
" adc %15,%15" "\n\t" /* %15:16 <<= 1*/
" adc %15,%15" "\n\t" // %15:16 <<= 1
"9:" "\n\t"
" sbrs %3,2" "\n\t" /* shift by 4bits position?*/
" rjmp 16f" "\n\t" /* No*/
" swap %15" "\n\t" /* Swap nibbles. lo nibble of %15 will always be 0*/
" swap %14" "\n\t" /* Swap nibbles*/
" sbrs %3,2" "\n\t" // shift by 4bits position?
" rjmp 16f" "\n\t" // No
" swap %15" "\n\t" // Swap nibbles. lo nibble of %15 will always be 0
" swap %14" "\n\t" // Swap nibbles
" mov %12,%14" "\n\t"
" andi %12,0x0f" "\n\t" /* isolate low nibble*/
" andi %14,0xf0" "\n\t" /* and clear it*/
" or %15,%12" "\n\t" /* %15:%16 <<= 4*/
" andi %12,0x0f" "\n\t" // isolate low nibble
" andi %14,0xf0" "\n\t" // and clear it
" or %15,%12" "\n\t" // %15:%16 <<= 4
"16:" "\n\t"
" sbrs %3,3" "\n\t" /* shift by 8bits position?*/
" rjmp 6f" "\n\t" /* No, we are done */
" sbrs %3,3" "\n\t" // shift by 8bits position?
" rjmp 6f" "\n\t" // No, we are done
" mov %16,%15" "\n\t"
" mov %15,%14" "\n\t"
" clr %14" "\n\t"
" jmp 6f" "\n\t"
/* idx < 8, now %3 = idx - 8. Get the count of bits */
// idx < 8, now %3 = idx - 8. Get the count of bits
"7:" "\n\t"
" neg %3" "\n\t" /* %3 = -idx = count of bits to move right. idx range:[1...8]*/
" sbrs %3,0" "\n\t" /* shift by 1 bit position ?*/
" rjmp 10f" "\n\t" /* No, skip it*/
" asr %15" "\n\t" /* (bit7 is always 0 here)*/
" neg %3" "\n\t" // %3 = -idx = count of bits to move right. idx range:[1...8]
" sbrs %3,0" "\n\t" // shift by 1 bit position ?
" rjmp 10f" "\n\t" // No, skip it
" asr %15" "\n\t" // (bit7 is always 0 here)
" ror %14" "\n\t"
"10:" "\n\t"
" sbrs %3,1" "\n\t" /* shift by 2 bit position ?*/
" rjmp 11f" "\n\t" /* No, skip it*/
" asr %15" "\n\t" /* (bit7 is always 0 here)*/
" sbrs %3,1" "\n\t" // shift by 2 bit position ?
" rjmp 11f" "\n\t" // No, skip it
" asr %15" "\n\t" // (bit7 is always 0 here)
" ror %14" "\n\t"
" asr %15" "\n\t" /* (bit7 is always 0 here)*/
" asr %15" "\n\t" // (bit7 is always 0 here)
" ror %14" "\n\t"
"11:" "\n\t"
" sbrs %3,2" "\n\t" /* shift by 4 bit position ?*/
" rjmp 12f" "\n\t" /* No, skip it*/
" swap %15" "\n\t" /* Swap nibbles*/
" andi %14, 0xf0" "\n\t" /* Lose the lowest nibble*/
" swap %14" "\n\t" /* Swap nibbles. Upper nibble is 0*/
" or %14,%15" "\n\t" /* Pass nibble from upper byte*/
" andi %15, 0x0f" "\n\t" /* And get rid of that nibble*/
" sbrs %3,2" "\n\t" // shift by 4 bit position ?
" rjmp 12f" "\n\t" // No, skip it
" swap %15" "\n\t" // Swap nibbles
" andi %14, 0xf0" "\n\t" // Lose the lowest nibble
" swap %14" "\n\t" // Swap nibbles. Upper nibble is 0
" or %14,%15" "\n\t" // Pass nibble from upper byte
" andi %15, 0x0f" "\n\t" // And get rid of that nibble
"12:" "\n\t"
" sbrs %3,3" "\n\t" /* shift by 8 bit position ?*/
" rjmp 6f" "\n\t" /* No, skip it*/
" sbrs %3,3" "\n\t" // shift by 8 bit position ?
" rjmp 6f" "\n\t" // No, skip it
" mov %14,%15" "\n\t"
" clr %15" "\n\t"
"6:" "\n\t" /* %16:%15:%14 = initial estimation of 0x1000000 / d*/
"6:" "\n\t" // %16:%15:%14 = initial estimation of 0x1000000 / d
/* Now, we must refine the estimation present on %16:%15:%14 using 1 iteration*/
/* of Newton-Raphson. As it has a quadratic convergence, 1 iteration is enough*/
/* to get more than 18bits of precision (the initial table lookup gives 9 bits of*/
/* precision to start from). 18bits of precision is all what is needed here for result */
// Now, we must refine the estimation present on %16:%15:%14 using 1 iteration
// of Newton-Raphson. As it has a quadratic convergence, 1 iteration is enough
// to get more than 18bits of precision (the initial table lookup gives 9 bits of
// precision to start from). 18bits of precision is all what is needed here for result
/* %8:%7:%6 = d = interval*/
/* %16:%15:%14 = x = initial estimation of 0x1000000 / d*/
/* %13 = 0*/
/* %3:%2:%1:%0 = working accumulator*/
// %8:%7:%6 = d = interval
// %16:%15:%14 = x = initial estimation of 0x1000000 / d
// %13 = 0
// %3:%2:%1:%0 = working accumulator
/* Compute 1<<25 - x*d. Result should never exceed 25 bits and should always be positive*/
// Compute 1<<25 - x*d. Result should never exceed 25 bits and should always be positive
" clr %0" "\n\t"
" clr %1" "\n\t"
" clr %2" "\n\t"
" ldi %3,2" "\n\t" /* %3:%2:%1:%0 = 0x2000000*/
" mul %6,%14" "\n\t" /* r1:r0 = LO(d) * LO(x)*/
" ldi %3,2" "\n\t" // %3:%2:%1:%0 = 0x2000000
" mul %6,%14" "\n\t" // r1:r0 = LO(d) * LO(x)
" sub %0,r0" "\n\t"
" sbc %1,r1" "\n\t"
" sbc %2,%13" "\n\t"
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= LO(d) * LO(x)*/
" mul %7,%14" "\n\t" /* r1:r0 = MI(d) * LO(x)*/
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= LO(d) * LO(x)
" mul %7,%14" "\n\t" // r1:r0 = MI(d) * LO(x)
" sub %1,r0" "\n\t"
" sbc %2,r1" "\n\t"
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= MI(d) * LO(x) << 8*/
" mul %8,%14" "\n\t" /* r1:r0 = HI(d) * LO(x)*/
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= MI(d) * LO(x) << 8
" mul %8,%14" "\n\t" // r1:r0 = HI(d) * LO(x)
" sub %2,r0" "\n\t"
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= MIL(d) * LO(x) << 16*/
" mul %6,%15" "\n\t" /* r1:r0 = LO(d) * MI(x)*/
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16
" mul %6,%15" "\n\t" // r1:r0 = LO(d) * MI(x)
" sub %1,r0" "\n\t"
" sbc %2,r1" "\n\t"
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= LO(d) * MI(x) << 8*/
" mul %7,%15" "\n\t" /* r1:r0 = MI(d) * MI(x)*/
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= LO(d) * MI(x) << 8
" mul %7,%15" "\n\t" // r1:r0 = MI(d) * MI(x)
" sub %2,r0" "\n\t"
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= MI(d) * MI(x) << 16*/
" mul %8,%15" "\n\t" /* r1:r0 = HI(d) * MI(x)*/
" sub %3,r0" "\n\t" /* %3:%2:%1:%0 -= MIL(d) * MI(x) << 24*/
" mul %6,%16" "\n\t" /* r1:r0 = LO(d) * HI(x)*/
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= MI(d) * MI(x) << 16
" mul %8,%15" "\n\t" // r1:r0 = HI(d) * MI(x)
" sub %3,r0" "\n\t" // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24
" mul %6,%16" "\n\t" // r1:r0 = LO(d) * HI(x)
" sub %2,r0" "\n\t"
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= LO(d) * HI(x) << 16*/
" mul %7,%16" "\n\t" /* r1:r0 = MI(d) * HI(x)*/
" sub %3,r0" "\n\t" /* %3:%2:%1:%0 -= MI(d) * HI(x) << 24*/
/* %3:%2:%1:%0 = (1<<25) - x*d [169]*/
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= LO(d) * HI(x) << 16
" mul %7,%16" "\n\t" // r1:r0 = MI(d) * HI(x)
" sub %3,r0" "\n\t" // %3:%2:%1:%0 -= MI(d) * HI(x) << 24
// %3:%2:%1:%0 = (1<<25) - x*d [169]
/* We need to multiply that result by x, and we are only interested in the top 24bits of that multiply*/
// We need to multiply that result by x, and we are only interested in the top 24bits of that multiply
/* %16:%15:%14 = x = initial estimation of 0x1000000 / d*/
/* %3:%2:%1:%0 = (1<<25) - x*d = acc*/
/* %13 = 0 */
// %16:%15:%14 = x = initial estimation of 0x1000000 / d
// %3:%2:%1:%0 = (1<<25) - x*d = acc
// %13 = 0
/* result = %11:%10:%9:%5:%4*/
" mul %14,%0" "\n\t" /* r1:r0 = LO(x) * LO(acc)*/
// result = %11:%10:%9:%5:%4
" mul %14,%0" "\n\t" // r1:r0 = LO(x) * LO(acc)
" mov %4,r1" "\n\t"
" clr %5" "\n\t"
" clr %9" "\n\t"
" clr %10" "\n\t"
" clr %11" "\n\t" /* %11:%10:%9:%5:%4 = LO(x) * LO(acc) >> 8*/
" mul %15,%0" "\n\t" /* r1:r0 = MI(x) * LO(acc)*/
" clr %11" "\n\t" // %11:%10:%9:%5:%4 = LO(x) * LO(acc) >> 8
" mul %15,%0" "\n\t" // r1:r0 = MI(x) * LO(acc)
" add %4,r0" "\n\t"
" adc %5,r1" "\n\t"
" adc %9,%13" "\n\t"
" adc %10,%13" "\n\t"
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * LO(acc) */
" mul %16,%0" "\n\t" /* r1:r0 = HI(x) * LO(acc)*/
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * LO(acc)
" mul %16,%0" "\n\t" // r1:r0 = HI(x) * LO(acc)
" add %5,r0" "\n\t"
" adc %9,r1" "\n\t"
" adc %10,%13" "\n\t"
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * LO(acc) << 8*/
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * LO(acc) << 8
" mul %14,%1" "\n\t" /* r1:r0 = LO(x) * MIL(acc)*/
" mul %14,%1" "\n\t" // r1:r0 = LO(x) * MIL(acc)
" add %4,r0" "\n\t"
" adc %5,r1" "\n\t"
" adc %9,%13" "\n\t"
" adc %10,%13" "\n\t"
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 = LO(x) * MIL(acc)*/
" mul %15,%1" "\n\t" /* r1:r0 = MI(x) * MIL(acc)*/
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 = LO(x) * MIL(acc)
" mul %15,%1" "\n\t" // r1:r0 = MI(x) * MIL(acc)
" add %5,r0" "\n\t"
" adc %9,r1" "\n\t"
" adc %10,%13" "\n\t"
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 8*/
" mul %16,%1" "\n\t" /* r1:r0 = HI(x) * MIL(acc)*/
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 8
" mul %16,%1" "\n\t" // r1:r0 = HI(x) * MIL(acc)
" add %9,r0" "\n\t"
" adc %10,r1" "\n\t"
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 16*/
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 16
" mul %14,%2" "\n\t" /* r1:r0 = LO(x) * MIH(acc)*/
" mul %14,%2" "\n\t" // r1:r0 = LO(x) * MIH(acc)
" add %5,r0" "\n\t"
" adc %9,r1" "\n\t"
" adc %10,%13" "\n\t"
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 = LO(x) * MIH(acc) << 8*/
" mul %15,%2" "\n\t" /* r1:r0 = MI(x) * MIH(acc)*/
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 = LO(x) * MIH(acc) << 8
" mul %15,%2" "\n\t" // r1:r0 = MI(x) * MIH(acc)
" add %9,r0" "\n\t"
" adc %10,r1" "\n\t"
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 16*/
" mul %16,%2" "\n\t" /* r1:r0 = HI(x) * MIH(acc)*/
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 16
" mul %16,%2" "\n\t" // r1:r0 = HI(x) * MIH(acc)
" add %10,r0" "\n\t"
" adc %11,r1" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 24*/
" adc %11,r1" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 24
" mul %14,%3" "\n\t" /* r1:r0 = LO(x) * HI(acc)*/
" mul %14,%3" "\n\t" // r1:r0 = LO(x) * HI(acc)
" add %9,r0" "\n\t"
" adc %10,r1" "\n\t"
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 = LO(x) * HI(acc) << 16*/
" mul %15,%3" "\n\t" /* r1:r0 = MI(x) * HI(acc)*/
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 = LO(x) * HI(acc) << 16
" mul %15,%3" "\n\t" // r1:r0 = MI(x) * HI(acc)
" add %10,r0" "\n\t"
" adc %11,r1" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 24*/
" mul %16,%3" "\n\t" /* r1:r0 = HI(x) * HI(acc)*/
" add %11,r0" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 32*/
" adc %11,r1" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 24
" mul %16,%3" "\n\t" // r1:r0 = HI(x) * HI(acc)
" add %11,r0" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 32
/* At this point, %11:%10:%9 contains the new estimation of x. */
// At this point, %11:%10:%9 contains the new estimation of x.
/* Finally, we must correct the result. Estimate remainder as*/
/* (1<<24) - x*d*/
/* %11:%10:%9 = x*/
/* %8:%7:%6 = d = interval" "\n\t" /* */
// Finally, we must correct the result. Estimate remainder as
// (1<<24) - x*d
// %11:%10:%9 = x
// %8:%7:%6 = d = interval" "\n\t"
" ldi %3,1" "\n\t"
" clr %2" "\n\t"
" clr %1" "\n\t"
" clr %0" "\n\t" /* %3:%2:%1:%0 = 0x1000000*/
" mul %6,%9" "\n\t" /* r1:r0 = LO(d) * LO(x)*/
" clr %0" "\n\t" // %3:%2:%1:%0 = 0x1000000
" mul %6,%9" "\n\t" // r1:r0 = LO(d) * LO(x)
" sub %0,r0" "\n\t"
" sbc %1,r1" "\n\t"
" sbc %2,%13" "\n\t"
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= LO(d) * LO(x)*/
" mul %7,%9" "\n\t" /* r1:r0 = MI(d) * LO(x)*/
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= LO(d) * LO(x)
" mul %7,%9" "\n\t" // r1:r0 = MI(d) * LO(x)
" sub %1,r0" "\n\t"
" sbc %2,r1" "\n\t"
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= MI(d) * LO(x) << 8*/
" mul %8,%9" "\n\t" /* r1:r0 = HI(d) * LO(x)*/
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= MI(d) * LO(x) << 8
" mul %8,%9" "\n\t" // r1:r0 = HI(d) * LO(x)
" sub %2,r0" "\n\t"
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= MIL(d) * LO(x) << 16*/
" mul %6,%10" "\n\t" /* r1:r0 = LO(d) * MI(x)*/
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16
" mul %6,%10" "\n\t" // r1:r0 = LO(d) * MI(x)
" sub %1,r0" "\n\t"
" sbc %2,r1" "\n\t"
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= LO(d) * MI(x) << 8*/
" mul %7,%10" "\n\t" /* r1:r0 = MI(d) * MI(x)*/
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= LO(d) * MI(x) << 8
" mul %7,%10" "\n\t" // r1:r0 = MI(d) * MI(x)
" sub %2,r0" "\n\t"
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= MI(d) * MI(x) << 16*/
" mul %8,%10" "\n\t" /* r1:r0 = HI(d) * MI(x)*/
" sub %3,r0" "\n\t" /* %3:%2:%1:%0 -= MIL(d) * MI(x) << 24*/
" mul %6,%11" "\n\t" /* r1:r0 = LO(d) * HI(x)*/
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= MI(d) * MI(x) << 16
" mul %8,%10" "\n\t" // r1:r0 = HI(d) * MI(x)
" sub %3,r0" "\n\t" // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24
" mul %6,%11" "\n\t" // r1:r0 = LO(d) * HI(x)
" sub %2,r0" "\n\t"
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= LO(d) * HI(x) << 16*/
" mul %7,%11" "\n\t" /* r1:r0 = MI(d) * HI(x)*/
" sub %3,r0" "\n\t" /* %3:%2:%1:%0 -= MI(d) * HI(x) << 24*/
/* %3:%2:%1:%0 = r = (1<<24) - x*d*/
/* %8:%7:%6 = d = interval */
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= LO(d) * HI(x) << 16
" mul %7,%11" "\n\t" // r1:r0 = MI(d) * HI(x)
" sub %3,r0" "\n\t" // %3:%2:%1:%0 -= MI(d) * HI(x) << 24
// %3:%2:%1:%0 = r = (1<<24) - x*d
// %8:%7:%6 = d = interval
/* Perform the final correction*/
// Perform the final correction
" sub %0,%6" "\n\t"
" sbc %1,%7" "\n\t"
" sbc %2,%8" "\n\t" /* r -= d*/
" brcs 14f" "\n\t" /* if ( r >= d) */
" sbc %2,%8" "\n\t" // r -= d
" brcs 14f" "\n\t" // if ( r >= d)
/* %11:%10:%9 = x */
// %11:%10:%9 = x
" ldi %3,1" "\n\t"
" add %9,%3" "\n\t"
" adc %10,%13" "\n\t"
" adc %11,%13" "\n\t" /* x++*/
" adc %11,%13" "\n\t" // x++
"14:" "\n\t"
/* Estimation is done. %11:%10:%9 = x */
" clr __zero_reg__" "\n\t" /* Make C runtime happy */
/* [211 cycles total]*/
// Estimation is done. %11:%10:%9 = x
" clr __zero_reg__" "\n\t" // Make C runtime happy
// [211 cycles total]
: "=r" (r2),
"=r" (r3),
"=r" (r4),

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